Hi,

I'm having an annoying issue with WWW::Mechanize::Firefox xpath() method. The following code...

#!perl -w
use strict;
use WWW::Mechanize::Firefox;
use Data::Dumper;

my $mech = WWW::Mechanize::Firefox->new(activate => 1);
$mech->autoclose_tab(0);
$mech->update_html(<<'HTML');
<html>
<head>
<title>Hello Firefox!</title>
</head>
<body>
<h1>Hello <b>World</b>!</h1>
<p id='paragraph'>Hello <b>WWW::Mechanize::Firefox</b> Goob bye</p>
</body>
</html>
HTML

test_xpath($mech, '//p', all => 1);
test_xpath($mech, '//p/text()', all => 1);
test_xpath($mech, 'substring(//p,1,4)', all => 1); # expected String: 
+Hell
test_xpath($mech, 'string-length(//p)', all => 1); # expected Number: 
+38

sub test_xpath {
  my ($mech, $xpq, %opts) = @_;
  my @xpr;
  eval { @xpr = $mech->xpath($xpq, %opts); };
  my %results = (
    query       => $xpq,
    exception   => $@,
    innerHTML   => scalar(@xpr) ? [ map { $_->{innerHTML}   } @xpr ] :
+ undef,
    textContent => scalar(@xpr) ? [ map { $_->{textContent} } @xpr ] :
+ undef,
    nodeValue   => scalar(@xpr) ? [ map { $_->{nodeValue}   } @xpr ] :
+ undef
  );
  print Data::Dumper->Dump([\%results], ['results']);
}

[download]

...shows that (sadly for now in v0.71) not all the Xpath results are handled by this nevertheless amazing module.

$results = {
             'nodeValue' => [
                              undef
                            ],
             'exception' => '',
             'query' => '//p',
             'textContent' => [
                                'Hello WWW::Mechanize::Firefox Goob by
+e'
                              ],
             'innerHTML' => [
                              'Hello <b>WWW::Mechanize::Firefox</b> Go
+ob bye'
                            ]
           };
$results = {
             'nodeValue' => [
                              'Hello ',
                              ' Goob bye'
                            ],
             'exception' => '',
             'query' => '//p/text()',
             'textContent' => [
                                'Hello ',
                                ' Goob bye'
                              ],
             'innerHTML' => [
                              undef,
                              undef
                            ]
           };
$results = {
             'nodeValue' => undef,
             'exception' => 'MozRepl::RemoteObject: TypeError: The exp
+ression cannot be converted to return the specified type. at mech.pl 
+line 28.
',
             'query' => 'substring(//p,1,4)',
             'textContent' => undef,
             'innerHTML' => undef
           };
$results = {
             'nodeValue' => undef,
             'exception' => 'MozRepl::RemoteObject: TypeError: The exp
+ression cannot be converted to return the specified type. at mech.pl 
+line 28.
',
             'query' => 'string-length(//p)',
             'textContent' => undef,
             'innerHTML' => undef
           };

[download]

I would be very interested with any workaround.

____
HTH, Dominique
My two favorites:
If the only tool you have is a hammer, you will see every problem as a nail. --Abraham Maslow
Bien faire, et le faire savoir...

In reply to Some issues with WWW::Mechanize::Firefox->xpath() method by dfaure

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